(Phys.org) —Artifacts from the Middle Stone Age, which lasted from about 200,000 to 50,000 years ago, provide us with the earliest glimpses of modern human art and culture. Previously, scientists thought an increase in ...

Climate change in the Arctic is more evident than in most parts of the world, with global warming moving at a rate of almost twice the global average. But this also has an effect on some parts of Europe, which is being investigated ...

The first-known definitive case of a benign bone tumor has been discovered in the rib of a young Neandertal who lived about 120,000 years ago in what is now present-day Croatia. The bone fragment, which comes from the famous ...

(Phys.org) —Many think of social networks in terms of Facebook friends and Twitter followers, but for recent University of Georgia doctoral graduate Julie Rushmore, social networks are tools in the fight against infectious ...

In 2010, in the journal Nature, a pair of physicists at the Santa Fe Institute showed that when the population of a city doubles, economic productivity goes up by an average of 130 percent. Not only does total productivity ...

(Phys.org) —Researchers designing adult bipedal robots have faced a challenge in limitations in a robot's walking pattern. They seek ways to improve on designs to have robots move more naturally. Improving the walking function ...

(Phys.org) —Marine scientists from Australia and the USA today called for global efforts to protect deeper coral reefs as insurance against the widespread destruction of shallow reefs and their fish stocks now taking place ...

By sequencing the genome of a Bactrian camel, researchers at the Vetmeduni Vienna have made a significant contribution to population genetic research on camels. The study has laid the foundation for future scientific work ...

World population

The term world population commonly refers to the total number of living humans on Earth at a given time. As of 29 July 2009, the Earth's population is estimated by the United States Census Bureau to be 6.774 billion. The world population has been growing continuously since the end of the Black Death around 1400. There were also short term falls at other times due to plague, for example in the mid 17th century (see graph). The fastest rates of world population growth (above 1.8%) were seen briefly during the 1950s then for a longer period during the 1960s and 1970s (see graph). According to population projections, world population will continue to grow until around 2050. The 2008 rate of growth has almost halved since its peak of 2.2% per year, which was reached in 1963. World births have levelled off at about 134-million-per-year, since their peak at 163-million in the late 1990s, and are expected to remain constant. However, deaths are only around 57 million per year, and are expected to increase to 90 million by the year 2050. Since births outnumber deaths, the world's population is expected to reach about 9 billion by the year 2040.